Window.Populate.cs

public static class Populate
{
    public static Window[] FromHandles(string[] handles)
    {
        var windows = new Window[handles.Length];

        for (int i = 0; i < windows.Length; ++i)
        {
            windows[i] = new Window(new IntPtr(Convert.ToInt32(handles[i])));
        }
        
        return windows;
    }

    public static Window[] FromHandles(IntPtr[] handles)
    {
        var windows = new Window[handles.Length];

        for (int i = 0; i < windows.Length; ++i)
        {
            windows[i] = new Window(handles[i]);
        }
        
        return windows;
    }
}

        public void Test()
        {
            string[] dataStr = new List<string>().ToArray();
            IntPtr[] data = new List<IntPtr>().ToArray();
            IEnumerable res1 = FromHandles((collection, i) => new Window(new IntPtr(Convert.ToInt32(collection.ElementAt(i)))), dataStr);
            IEnumerable res2 = FromHandles((collection, i) => new Window(collection.ElementAt(i)), data);
        }


        public static ICollection<Window> FromHandles<T>(Func<IEnumerable<T>, int, Window> windowCreator, IEnumerable<T> data)
        {
            var windows = new Window[data.Count()];
            for(int i = 0; i< data.Count(); ++i)
            {
                windows[i] = windowCreator(data, i);
            }
            return windows;
        }